Windows/Motif L&F: Changing the JComboBox background does not change the popup of the JCombobox

Aim of the program :- to change the background color of the JComboBox

 Step to reproduce
 1) start the program.
 2) Select Look And Feel Menu & select Motif Look and Feel MenuIem .
 3) Select Color Menu & select Background Color Menuitem. You can see background color of JComboBox is changed (the value & down arrow button).
 4) Click on the JComboBox , the popupMenu of JComboBox color is not changed.
      Expect result :- The whole JComboBox is supposed to Change including the popupMenu.
 5) Click on look & feel Menu & Java look & feel menuitem , you can see the color is changed for the whole JComboBox including the popupMenu.
 6) Once again Click on Look And Feel Menu & select Motif Look and Feel MenuIem. Now the
    whole JComboBox including the popupMenu is changed to the specified background color.

   I have attached the sample program.

  I tested this program with build 64 in mustang & in tiger rc build 63 it results same.